Spotify is heading to mobile phones, with the developers of the ad-supported free music service already working on a mobile version of the software.

Spotify recently employed ex-Yahoo man Gustav Söderström to head up the development and marketing of the web-based music streaming service.

Söderström notes on his blog this week that Spotify will be available for mobile phones, but gives no indication of when it will be made available.

Instant, free music anywhere

The idea of instant, free music from Spotify's massive library is enough to excite any self-respecting tech fan, although there was slight concern earlier this month that some labels and artists were pulling tunes off the service.

However, the mere fact that Spotify has taken on the ex-Yahoo man to run the show surely means that the service is here to stay. We'll be keeping a very close eye on all developments over at Spotify and keep you updated.